Oriental Stork Ciconia boyciana 東方白鸛
Category I. Rare winter visitor to wetland areas in northwest New Territories.
IDENTIFICATION
Oct. 2012, Martin Hale.
110-115 cm. Very large, long neck and legs. All white apart from black flight feathers, the secondaries and inner primaries of which have whitish inner webs. Distinctive deeply-based bill with rather straight culmen and slightly upcurved lower mandible.
Sep. 2012, Michelle and Peter Wong.
In flight long bill and legs, broad wings with deep fingers and black flight feathers contrasting with white underwing coverts and body.
VOCALISATIONS
Appears to be silent away from the breeding grounds.
DISTRIBUTION & HABITAT PREFERENCE
Most records have occurred in the Deep Bay area, mainly at Mai Po NR which is the least disturbed large area of wetland present. Also recorded at the Lok Ma Chau MTRC wetland mitigation area, and there is one record of a bird soaring over hills at Pak Nai.
OCCURRENCE
Up to 2020 there were fewer than 20 records of Oriental Stork in HK, albeit some referred to long-staying individuals or groups. The first occurred on 5th and 12 February 1967, and the second on 27 October 1979 and from 16 December 1979 to 9 April 1980. There were a further eight records in the nine-year period from February 1987 to February 1996, the most significant of which was a flock of up to 121 birds that remained from 27 November to 10 March 1991 (Chan 1991). It is likely that some birds (first-years?) from this flock returned in subsequent winter periods, with the highest count being 16 in winter 1992-93, which fell to one in winter 1995-96.
The next bird occurred on 31 December 1999, and since then there have been five records, the most unusual of which is a first-year that remained from 12 July 2012 to 3 March 2013. During this recent period no more than two birds have been recorded.
A first-year bird bearing a yellow ring seen at Mai Po NR from 31 December 1999 to 9 March 2000 was ringed as a chick on 6 July 1999 at Bolon Lake, Khabarovsk, Russia.
BEHAVIOUR, FORAGING & DIET
No observations.
RANGE & SYSTEMATICS
Monotypic. Breeds in northeast China and Ussuriland, and winters in southeast and east China, South Korea and Japan (Elliott et al. 2020).
CONSERVATION STATUS
IUCN: ENDANGERED. Population size 1,000 to 2,499 individuals and decreasing due to deforestation, wetland reclamation for agriculture, overfishing and disturbance.
Chan, S. (1991). The Historical and Current Status of the Oriental White Stork. Hong Kong Bird Report 1990: 128-148.
Elliott, A., G. M. Kirwan, and E. F. J. Garcia (2020). Oriental Stork (Ciconia boyciana), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.oristo1.01
